T-Mobile US’ stock jumped as much as 5% on Friday on reports that SoftBank, the Japanese telecom company that owns Sprint, was looking to make another run at it.

Reuters reported the news on Friday afternoon.

SoftBank has not yet approached Deutsche Telekom, which owns T-Mobile US, according to the report.

For regulatory reasons, the two companies will be able to begin negotiations in April, the report said.

This would be the second time Softbank has made an effort to acquire T-Mobile.

It explored the idea in 2014, only to back down after telecom regulators made it clear they would block any acquisition of the fourth-largest US carrier.

In 2011, AT&T struck a $39 billion deal to acquire T-Mobile, but walked away after facing the same objections from the Federal Communications Commission and Department of Justice.

Regulators under the Obama Administration had objected to the tie-up out of concern that eliminating a major competitor in the telecom market would be bad for consumers.

A change in the government could give SoftBank’s CEO, the Japanese billionaire Masayoshi Son the opening he needs. In December he met with President Trump, who announced he’d pledged to create 50,000 new jobs in the US. The investment is actually from the SoftBank Vision Fund and was announced in October.

In August, Bloomberg News reported that Son was likely to make another run at Sprint if the new FCC head seemed more amenable to it.

SoftBank is a highly acquisitive company. On Tuesday it announced it was buying the asset manager Fortress Investment Group for $3.3 billion.